Special MRI (MWI, MTI, G-ratio) methods sensitive to age and development

Abstract Early pediatric neurodevelopment is marked by rapid growth and development of every structural and functional brain system and network. Fundamental processes, including synaptogenesis and synaptic pruning, and myelination work in competitive collaboration to build functional brain networks that support nearly every cognitive function and behavioral skill. MRI provides a noninvasive means with which to measure these evolving structural and functional connections and networks. Techniques such as quantitative relaxation time measurement, magnetization transfer imaging, and multicomponent water imaging provide important and quantitative insight into the maturing tissue microstructure and myelination processes. In this chapter, we outline these quantitative techniques, including methods to collect the data and potential pitfalls and areas of opportunity and forth advancement.